Moscow is to replace Microsoft products with Russian software as part of President Putin's plan to reduce the country's dependency on foreign technology.
The city's authorities have already replaced Cisco networking software with a domestic equivalent, and Oracle databases have been swapped out for open source PostgreSQL at Moscow's regional government and state-owned media firm Rossiya Segodnya, Bloomberg reported.
Artem Yermolaev, Moscow's technology chief, explained that the city will begin by dropping Microsoft Exchange Server and replacing Outlook with an email system developed by state-run carrier Rostelecom on 6,000 computers. This will be expanded to 600,000 computers in the future.
Yermolaev hinted to reporters that Windows and Microsoft Office may also be replaced.
Putin has urged Russian organisations for some time to opt for local technology. He accused US corporations of closing down services in Crimea after Russia annexed the territory in 2014, although there is little evidence that this occurred.
The Russian government is no doubt using the allegation to promote local technology and to play on anti-US sentiment in the country.
Russian internet chief German Klimenko reportedly wants to increase taxes imposed on US firms operating in Russia.
"We want the money of taxpayers and state-run firms to be primarily spent on local software," communications minister Nikolay Nikiforov told reporters.
He added that from next year the Federal Anti-Monopoly Service, General Prosecutor's Office and Audit Chamber "will tighten their grip" on state institutions that fail to switch to domestic alternatives.
The Putin government recently passed a number of laws relating to the technology sector. Russian websites have been required to store data about visitors since 2014, and measures have been taken to enforce backdoors against encryption.
Similar measures to require storage of information and to limit encryption are included in the UK Investigatory Powers Bill, which is currently being scrutinised in the House of Lords.
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